A clever cross between castle defence and twin-stick shooter, Bug Heroes consists of as many individual segments as the insects that star in this amusing game.

Considered individually, each element is simple - almost prosaic - but together they form a diverse whole that offers fun and variety in equal measure.

It's an original game with the right balance between action and strategy, which yields both immediate satisfaction and long term value. Bug Heroes demonstrates that tired ideas can be renewed when massaged with creativity and attention to detail.

A bug's life

Placed on the front line in a massive insect war, you control three bugs - an ant, a beetle, and a spider - against waves of hungry creepy crawlers. These insect swarms are eager to make a beeline for your private cache of food, which you must defend to the death.

You do this by surrounding your food pile with defensive weapons and sending out your three bug heroes to attack encroaching enemies. Cash is earned for bugs squashed, which you can use to purchase turrets that automatically defend your food. Investing additional funds into existing turrets increases their effectiveness. Money can also be used to unlock better weapons and new abilities for your heroes.

Learning how to leverage each of the heroes is key. The ant, for instance, excels at long range combat thanks to his miniature rifle that can be upgraded to a death-dealing machine gun. Switching to the beetle is useful for clearing groups of grubs or fleas with his sweeping staff attack. Lastly, the spider's sharp blades and speedy movement allow for devastating assaults against the strongest insect foes.

Beauty is only exoskeleton deep

This straightforward combination of castle defence and twin-stick shooter gameplay is fun, fast, and challenging. By infusing defensive gameplay with real-time action, Bug Heroes feels more involved than either element taken on its own. Rather than managing the defence of your food from afar, you're actively engaged in its protection and this makes for a more engaging experience.

The ability to purchase defences, upgrade your heroes with new equipment and skills, and even improve their core attributes using experience earned from kills provides much-needed depth. Bug Heroes is a high score chasing game at its core, yet it feels substantial thanks to these upgrade options.

As a way of keeping the game fresh, optional objectives are periodically offered for bonus experience, cash, and food. Even after you've cleared the four levels in Adventure mode and tested your mettle in the Coliseum, you can retry levels and take on these side missions for more of a challenge.

The flies in the ointment

Racking up points is also a reason to replay, although Bug Heroes uses a proprietary leaderboard rather than tapping into an existing social gaming network. Game Center or OpenFeint integrated would be preferable. This would also give more weight to the in-game awards.

Two minor criticisms deserve attention. First, the game features a day-night cycle that does much to highlight the nice graphics, but has no substantive role in gameplay. It's a novelty that could be stripped without impact. [NOTE: The day-night cycle does affect the availability of a high level turret, enemy, and special ability. While it was incorrect to state that it has no role in gameplay, it has a minor role that only becomes evident late in the game.]

Second, the structure of each wave is ambiguous. It's tough to know the size of a wave until the bugs appear. Often a wave seems finished because the screen is clear, but a flea will bound in or you missed an insect camping out in a corner. An indicator of the number of bugs in each wave would resolve this.

These are easily addressed complaints that have a small impact on the game as a whole. Bug Heroes is more than the sum of its simple parts, delivering fun and variety with its creative gameplay blend.